Automatic bag opener



. March 1969 M. MANFREDONIA ETAL 3,430,409

AUTOMATIC BAG OPENER ofB Sheet Filed April 20, 1967 FIG! INVENTORS FIGZ 26 2i w gas 2| 26 I EDWARD 0. WILCOX MARIO MANFREDONIA BY M I M ATTORNEY March 1969 M. MANFREDONIA ETAL 3,430,409

AUTOMATIC BAG OPENER Filed April 20, 1967 sheei a of 2 INVENTORS EDWARD D. WILCOX MARIO MANFREDONIA H BY 4% m ATTORNEY United States Patent 3,430,409 AUTOMATIC BAG OPENER Mario Manfredonia, Glen Cove, and Edward D. Wilcox,

Jr., New York, N.Y., assignors to Union Camp Corporation, New York, N.Y., a corporation of Virginia Filed Apr. 20, 1967, Ser. No. 632,369

U.S. Cl. 533 12 Claims Int. Cl. B65b 43/30 ABSTRACT OF THE DISCLOSURE An apparatus for opening the mouth of a bag. A plurality of vacuum cups are positioned adjacent one side of the bag. A centrally located vacuum cup is retracted causing a portion of one side of the bag to move with it. The movement of a portion of one side of the bag disrupts the planar parallel relationship between the sides of the bag, thereby opening it.

Specification The present invention relates to a method and apparatus for opening bags and more particularly to a method and apparatus for opening the mouth of a bag and subsequently positioning said bag to be filled.

Over the years many types of assembly lines have been developed for the filling of flexible bags in an automatic manner. However, despite the speed of the automatic bag filling machines, the filling of bags on an assembly line has been plagued by the difficult and time consuming operation of separating the adjacent bag walls in order to open the mouth portions of the bags for filling purposes. This problem is particularly vexing when the bags are supplied in stacks and have to be removed from the stack one at a time before they can be opened. Presently, when the bags are supplied in stacks, one bag must first be removed from the stack and then a suction means is applied to opposing walls of the bag causing the walls to separate and the mouth portion to open. Prior art apparatus, therefore, required complex, expensive and cumbersome feeding means for removing one bag at a time from the stack in order to open it. The bag separating and feeding apparatus in many instances comprised an entirely separate machine which had to be relocated and associated with different bag opening and filling machines.

One such separate bag feeding machine is illustrated in Allen U.S. Patent No. 2,332,187 wherein a single bag is removed from the stack by one machine and then fed to a separate bag opening and filling machine. Because of the necessity of feeding individual bags to existing bag opening apparatus, such apparatus tends to be too slow and inefficient for use on automatic assembly lines.

The present invention solves this problem by providing an integral bag separating, opening and positioning apparatus wherein a single bag can be removed from a supply stack and opened in a single operation.

An object of this invention is to provide an improved apparatus for opening the mouth of a bag.

Another object is to provide an apparatus for positioning a bag about a filling nozzle after opening the bag.

Another object is to provide a novel apparatus for opening the top bag in a supply stack without removing the bag from the stack.

Another object is to provide an improved bag opening apparatus that is highly efiicient and automatic in operation and extremely simple and economical in construction.

Another object is to provide a method of opening the mouth of a bag.

Another object is to provide an improved method of 3,430,409 Patented Mar. 4, 1969 opening the mouth of a bag and positioning the opened bag about a filling means.

Another object is to provide a method of opening the mouth portion of the top bag in a supply stack without removing the bag from the stack.

Other objects of the invention will in part be obvious and will in part appear hereinafter.

The invention accordingly comprises the several steps and the relation of one or more of such steps with respect to each of the others, and the apparatus embodying features of construction, combinations of elements and arrangement of parts which are adapted to effect such steps, all as exemplified in the following detailed disclosure, and the scope of the invention will be indicated in the claims.

For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description taken in connection with the accompanying drawings, in which:

FIGURE 1 is a front view of the bag opener in its retracted position;

FIGURE 2 is a front view of the bag opener in its extended position;

FIGURE 3 is a front view of the bag opener opening a bag upon returning to its original retracted position; and,

FIGURE 4 is a side view of the bag opener positioning the opened bag about a filling means.

Referring now to the drawings wherein like reference numerals designate like or corresponding parts throughout the several views, there is shown in FIGURE 1 a bag opening apparatus 10 having pivotally mounted actuating member 11, the member 11 having a shaft 12 adapted to extend or retract in a longitudinal direction when the member 11 is energized by a suitable source of power, such as fluid or electrical.

Mounted on the member 11 intermediate its ends is a guide collar 14 having a guideway 15 therein. The guideway 15 extends through the collar 14 and is substantially coaxial to the longitudinal axis of the member 11. A limit switch 20 for electrically controlling a source of vacuum (not shown) is mounted on the collar 14. The limit switch 20 can be any commercially available switch having an on and off position.

A support plate 13 is secured to the end of the member 11 through which the shaft 12 extends. The opposite end of the member 11 is pivotally mounted to a frame (not shown) by a pivot pin 31, as shown in FIGURE 4. The support plate 13 extends laterally from the member 11 and has a pair of adjustable cam rods 16 extending coaxially to the longitudinal axis of the member 11. The cam rods 16 are adjustable in a longitudinal direction and are disposed in a common plane on opposite sides of the member 11.

A pivot block 17 is secured to the end of the shaft 12 which extends from the member 11. The pivot block 17 is adapted to move toward and away from the member 11 when the shaft 12 is retracted and extended respectively. When the shaft 12 is in its original or retracted position, as shown in FIGURE 1, the pivot block 17 is adjacent the support plate 13. Extending upwardly from the block 17 is a guide rod 18. The guide rod 18 extends coaxially to the longitudinal axis of the member 11 and passes through the guideway 15 in the guide collar 14. As the shaft 12 is extended and retracted causing the pivot block 17 to move toward and away from the member 11, the guide rod 18 reciprocates through the guideway 15, providing a stabilizing guide means for the block 17. Disposed on the guide rod 18 intermediate its ends is a finger 19. The finger 19 extends laterally from the guide rod 18 and is adapted to actuate the switch 20 mounted on the collar 14 when the shaft 12 and the pivot block 17 are in their retracted position.

Extending outwardly from the pivot block 17 are a pair of pivot arms 21. The pivot arms 21 are pivotally mounted to the pivot block 17 on one end and extend coplanar to the cam rods 16. When the pivot block 17 is in its retracted position, the pivot arms 21 abut their respective cam rods 16. By adjusting the cam rods 16 in a longitudinal direction, the pivot arms 21 are forced downwardly at an acute angle to the plane of the pivot block 17. The angular position of the pivot arms 21 can be regulated by the adjustment of the cam rods 16.

Secured to the member 11 intermediate its ends and above the guide collar 14 are a pair of spring posts 23. The spring posts 23 are substantially L-shaped and extend outwardly from the member 11 with their short legs extending upwardly coaxial to the longitudinal axis of the member 11. A spring 24 is connected on one end to each of the spring posts 23 and on its opposite end to each of the pivot arms 21 at a point intermediate their ends. The springs 24 apply a force to the pivot arms 21 causing them to be held in abutting engegement with the cam rods 16.

A first vacuum cup 25 is mounted to the lowermost surface of the pivot block 17 and is connected to a constant source of vacuum through a vacuum line 27. A second vacuum .cup 26 is mounted on the free end of each of the pivot arms 21 and is connected to a source of vacuum through a vacuum line 33. The switch 20 is electrically connected to the source of vacuum for the second vacuum cup 26 and is adapted to control the flow of vacuum through the line 33.

In operation, when the shaft 12 is in its inactivated or retracted position as shown in FIGURE 1, the finger -19 is in actuating engagement with the switch 20. When the finger 19 is in actuating engagement with the switch 20, the switch is in its on position and vacuum is flowing through the line 33 to the cups 26. In this position, the pivot arms 21 are in abutting engagement with the cam rods 16. Since the cam rods 16 are adjusted until their lower ends are below the plane of the pivot block 17, the pivot arms 21 are forced downwardly at an acute angle to the plane of the block 17 against the restraining force of the springs 24.

FIGURE 2 shows the shaft 12 in its fully extended position. The application of a source of power to the member 11 causes the shaft 12 to extend in a longitudinal direction carrying the pivot block 17 with it. The movement of the pivot block -17 away from the member 11 causes the guide rod 18 to advance through the guideway 15, thereby breaking the actuating engagement between the finger 19 and the switch 20. When the contact between the finger 19 and the switch 20 is broken, the switch assumes its condition and stops the flow of vacuum through the line 33 to the second vacuum cups 26. As mentioned hereinbefore, the vacuum cup 25 has a constant source of vacuum applied to it at all times through the vacuum line 27. As the block 17 moves away from the member 11, the pivoted ends of the pivot arms 21 are forced downwardly against the tension of the springs 24 until the arms 21 are coplanar with the block 17. When the arms 21 and the block 17 are coplanar, a parallel stop 28, secured to the top of the pivot arms 21, overlaps and abuts the upper surface of the pivot block 17, preventing the pivot arms 21 from moving beyond the plane of the pivot block 17 which is a substantially horizontal plane.

When the shaft 12 is fully extended, the first vacuum cup 25 contacts a bag 29 located on top of a stack of bags located in a storage hopper 30. The vacuum cup 25 contacts the bag 29 along the central portion of one side adjacent its mouth. When the first vacuum cup 25 contacts the bag 29, the suction force of the vacuum at the cup 25 causes the portion of the bag 29 in juxtaposition with the cup 25 to adhere thereto. Since the second or outboard cups 215 are coplanar to the first or central cup 25, the cups 26 are also brought into contact with the bag 29 along the outer portions thereof. However, since there is no vacuum transmitted to the cups 26 at this movement, the portions of the bag 29 in juxtaposition to the cups 26 are not held in engagement to the cups 26.

After the suction force at the central vacuum cup 25 has caused the central portion of the bag 29 to adhere thereto, the shaft 12 is retracted causing the pivot block 17 and the cup 25 to move back toward the member 11. As the cup 25 moves away from the storage hopper 30, the suction force of the cup 25 causes the central portion of the engaged side of the bag 29 to move with it. At times, because of the porosity of the paper or for other reasons, it has been found that the cup 25 causes both the engaged side and the opposite side of the bag to move away from the storage hopper. In such cases a. conven tional hold down finger (not shown) can be used to hold the opposite side down while the engaged side is being raised.

The retraction of the shaft 12 and the block 17 to their original position causes the pivot arms 21 to abut the cam rods 16 forcing them out of their coplanar position relative to the block 17. Since the cam rods 16 are adjustable, the 'length of the rods 16 extending below the plane of the retracted block 17 can be regulated. When the pivot arms 21 are in abutting engagement with the lowermost ends of the cam rods 16, the pivot arms 21 are forced downward at an acute angle to the plane of the block 17. The angle of the arms 21 relative to the plane of the block 17 can be varied by adjusting the length of the cam rods 16 extending below the plane of the block 17 The greater the length of the cam rods 16 extending below the plane of the block 17, the greater will be the downward angle of the pivot arms 21. Since the cups 26, mounted on the ends of the pivot arms 21, are in abutting engagement to the outer portions of the bag 29, the central portion of the bag, which is engaged 'by the vacuum cup 25, travels a greater distance than the outer portions, thereby causing the mouth of the bag 29 to open as shown in FIGURE 3.

As the shaft 12 retracts, the pivot arms 21 abut the cam rods 16 prior to the block 17 reaching its fully retracted position. Because the central portion of the bag 29 is adhered to the cup 25 by the suction force, the central portion of the bag moves with the cup 25 and the outer portions of the bag 29 slide over the vacuum cups 26 against the frictional resistance thereof. The length of the pivot arms 21 are predetermined so that when the shaft is fully retracted, the outer portions of the bag 29' are in juxtaposition to the cups 26. At this point, the central portion of the bag 29 has traveled a greater distance than the outer portions and the engaged side of the bag assumes a tent-like configuration. When the shaft 12 is fully retracted, the finger 19 again contacts the switch 20 causing a vacuum to be applied to the cups 26 which causes the outer portions of the bag 29 in juxtaposition to the cups 26 to adhere thereto.

When the bag 29 is securely engaged by the suction force at the vacuum cups 25 and 26 and thereby maintained in its open tent-like configuration, the member 11 is pivoted about the pivot pin 31 as shown in FIGURE 4. The member 11 is pivoted approximately degrees from a vertical to a horizontal position. Since the bag 29 is securely held to the cups 25 and 26 by the suction force, the bag 29 in its open condition is transferred from its horizontal position to a vertical position. The amount of pivotal movement of the member 11 is dependent upon the height of a spout 32 relative to the pivot pin 31. The member 11 is pivoted about the pin 31 by any Well known means, such as an actuating cylinder, until the open mouth of the bag 29 is brought into juxtaposition to the spout 32. When the bag has been applied to the spout, it can be secured by bag clamps or other conventional means so that the bag can be filled. After the bag has been so secured, the member 11 moves to its starting position to pick up another bag from the stack.

While the apparatus has ben described for use in opening bags when they are stacked in a horizontal position, the apparatus is also capable of opening bags when they are stacked in a vertical position.

Since certain changes in carrying out the above process and in the construction set forth, which embody the invention, may be made without departing from its scope, it is intended that all matter contained in the above de scription or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.

Having described our invention, what we claim as new and desire to secure by Letters Patent is:

1. An apparatus for opening the mouth portion of a bag comprising:

a first vacuum means positioned in spaced relationship to one side of said bag;

means for advancing said vacuum means into contact with the central portion of said bag and retracting said vacuum means back to its spaced position;

means for applying a vacuum to said first vacuum means whereby said bag is retained in contact with said first vacuum means;

a second vacuum means pivotally secured to said first vacuum means and adapted to contact the outer portion of said bag when said first vacuum means contacts the central portion of said bag; and

means for pivoting said second vacuum means towards said bag when said first vacuum means is retracted whereby said central portion of one side of said bag moves a greater distance than the outer portions thereof causing the mouth of said bag to open.

2. An apparatus in accordance with claim 1, wherein said means for pivoting said second vacuum means comprises a cam rod disposed substantially perpendicular to the plane of said first vacuum means and in abutting alignment to said second vacuum means, said cam rod extending beyond the plane of said first vacuum means towards said bag when said first vacuum means is in its retracted position, whereby said cam rod abuts said second vacuum means when said first vacuum means is retracted causing said second vacuum means to be angularly disposed relative to the plane of said first vacuum means.

3. An apparatus in accordance with claim 1, further comprising means for applying a vacuum to said second vacuum means said first vacuum means is fully retracted.

4. An apparatus in accordance with claim 3, wherein said means for applying a vacuum to said second vacuum means comprises:

a source of vacuum;

a switch electrically connected to said source of vacuum for regulating the fiow of vacuum therefrom; and

a finger mounted to said means for advancing and retracting said vacuum means, said finger adapted to energize said switch when said first vacuum means is in its fully retracted position, whereby said energized switch permits the flow of vacuum to said second vacuum means when said first vacuum means is fully retracted.

5. An apparatus in accordance with claim 1, wherein said first vacuum means comprises a pivot block secured to said means for advancing and retracting said vacuum means and a vacuum cup mounted to said pivot block adjacent said bag, said vacuum cup having a constant source of vacuum applied thereto.

6. An apparatus in accordance with claim 5, wherein said second vacuum means comprises a pivot arm pivotally secured on one end to said pivot block, means secured to said pivot arm for urging said pivot arm into coplanar relationship to said pivot block and a vacuum cup secured to the free end of said pivot arm adjacent said bag, said vacuum cup adapted to contact the outer portion of said bag when said vacuum cup of said first vacuum means contacts the central portion of said bag.

7. An apparatus for opening the mouth portion of a bag comprising:

a pivotally mounted actuating member;

a shaft adapted to be advanced toward said bag or retracted away therefrom by said actuating member;

a first vacuum means secured to said shaft for movement therewith, said first vacuum means positioned to contact the central portion of said bag when said shaft is advanced; means for applying a vacuum to said first vacuum means whereby said bag is retained in contact with said first vacuum means during contact and subsequent retraction; second vacuum means pivotally secured to opposite sides of said first vacuum means and adapted to contact the outer portions of said bag when said first vacuum means contacts the central portion of said bag; means for urging said second vacuum means into coplanar relationship to said first vacuum means;

means for applying a vacuum to said second vacuum means when said first vacuum means is fully retracted; and

adjustable means disposed substantially perpendicular to the plane of said first vacuum means and in abutting alignment to said second vacuum means, said adjustable means extending beyond the plane of said first vacuum means towards said bag when said first vacuum means is fully retracted, said adjustable means abutting said second vacuum means when said first vacuum means is retracted causing said second vacuum means to pivot towards said bag against the urging of said adjustable means, whereby said central portion of one side of said bag moves a greater distance than the outer portions thereof causing the mouth of said bag to open.

8 An apparatus in accordance with claim 7, further comprising means for pivoting said actuating member and said open mouth bag into a filling position.

9. A method of opening the mouth portion of a bag comprising the steps of:

advancing a vacuum means into contact with the central portion of one side of said bag; applying a vacuum through said vacuum means to said central portion of said bag in contact with said vacuum means whereby said contacted portion of said bag securely adheres to said vacuum means;

advancing an inactive vacuum means into contact with the outer portions of said side of said bag;

retracting said vacuum means away from said bag relative to said inactive vacuum means, whereby said central portion of said side of said bag moves a greater distance than the outer portions thereof causing the mouth of the said bag to open.

10. A method of opening the mouth portion of a bag comprising the steps of:

contacting the central and outer portions of one side of said bag with a plurality of pivotally connected vacuum means;

applying a vacuum force to said vacuum means contacting said central portion of said bag, whereby said centrally contacted portion of said bag adheres to said vacuum means;

moving said vacuum means contacting said central portion of said bag away from said bag; and pivoting said vacuum means contacting the outer portions of said bag toward said bag while said centrally contacting vacuum means is moving away from said bag, whereby said central portion of said contacted side of said bag moves a greater distance than said Outer portions of said contacted side causing said mouth portion of said bag to open.

11. A method in accordance with claim 10, further comprising the step of applying a vacuum to said vacuum means contacting said outer portions of said bag when said centrally contacting vacuum means has moved away from said bag.

12. A method in accordance With claim 11, further comprising the step of pivoting said central and outer contacting vacuum means and said open mouth bag adhering thereto to a filling position whereby said open mouth bag is disposed in a plane different from its original plane.

References Cited UNITED STATES PATENTS 6/1954 Dolman 53386 X 3,287,879 11/1966 Miller 53386 X US. Cl. X.R. 

